Expansion tank



July 18, 1939. E. s. CORNELL. JR

EXPAN S ION TANK Filed May 29, 19:57

- INVENTOR ard 5. Cor

cooperating male threaded plug l4l.

Patented July 18, 1939 UNITED STATES EXPANSION TANK Edward S. Cornell, Jr., Larchmont, N. Y., as-

si'gnor, by mesne assignments, to American Radiator & Standard Sanitary Corporation, New York, N. Y., a corporation of Delaware Application May 29, 1937, Serial No. 145,531

2 Claims.

This invention relates to expansion tanks intended primarily for use with hot water heating systems of the atmospheric or open tank type.

In general, an object of the invention is to provide in an expansion tank, valve means automatically controlling the supply of make-up water to the tank whereby the contents thereof are maintained substantially at a predetermined level; and, further, to provide for access to such valve means from the exterior of the tank, and for closure of the means of access to guard against accumulation of dust and dirt in the tank during normal operation.

More particularly, the invention is directed to a' tank equipped with suitable valve means for automatically controlling the supply of liquid to the tank and shutting-off such supply upon the level of the liquid within the tank attaining a predetermined level height, combined with suitable overflow means connected in lateral relation with the tank below such predetermined level height, such overflow means extending upwardly to a height appreciably higher than such predetermined level height, whereby under conditions of variation of temperature of the liquid and resulting expansion and contraction of the liquid, accompanied by consequent rise and fall of the level of the liquid within the tank, such overflow means accommodates such rise and fall of the liquid for a predetermined range thereof and effects discharge of the liquid in excess of such range.

In the drawing which illustrates one embodiment of the invention,

Fig. 1 represents a vertical section taken centrally through an expansion tank embodying the features of the invention. One form of valve means appears in elevation.

Fig. 2 is a top plan view of one end portion of the expansion tank of Fig. 1.

Fig. 3 represents a left-end elevation of the tank of Fig. 1.

Referring to the drawing; as illustrated, the expansion tank in is preferably of cylindrical configuration and is formed advantageously from sheet metal, usually a copper alloy. The cylindrical body portion l I of the tank I!) has cupped end plates I2 and I3 respectively, of uniform size and shape, and arranged to be secured in place as by welding. The end plate [2 may have incorporated therewith at its center, a female threaded fitting I4 which may be closed by the The end plate l3 may have incorporated therewith at its center, the female threaded fitting 15 carrying in threaded relation therewith, the S-shaped pipe coupling |5I which extends upwardly for connection with suitable overflow piping.

As shown, the tank I0 is intended for horizontal positioning, and at the bottom of the cylindrical body portion H of the tank [0, a female threaded adaptor-fitting I6 is incorporated in the tank wall and has threaded within its outer end, the water supply pipe I 1.

Valve means of the ball-float type is disposed within the tank for automatically controlling the supply of water thereto. In the instant case, the valve mechanism per se, indicated at I8, is a conventional type for use with ball-float valves. It is supported near the top of the interior of the tank lil by the short pipe [9 which has its bottom end threaded into the inner end of the female threaded adaptor-fitting It, in" flow alignment with the water supply pipe ll.

The lever arm 26 for the valve mechanism I8 advantageously slopes downward toward the axial center of the tank, indicated by the dotted line X, and carries at'its free end the ball-float Elk-l. It should be noted that closure of the valve mechanism l8 takes place in a zone between the axial center of the tank and a point suitably below the upper bend of the S-shaped pipe coupling |5--i which connects the tank with overflow piping. The normal level of the water in the tank, i. e., the tank-water level within the normal heating system operating temperature range, occurs between the axial center of the tank and the upper bend of the S-shaped coupling.

For access to the valve assembly within the tank In for replacement or repair of the whole or any of the component parts thereof, an aperture 2! is formed in the upper wall of the cylindrical body It adjacent the valve mechanism l8. The aperture must be of sufiicient area to allow freedom of entrance into the interior of the tank of the component parts of the valve assembly and of their manipulation within the tank by a workman.

Normally, during operation of a heating system of which the tank Ill may form a component part, the access opening 2| is sealed by the cover plate 22 which conforms in configuration to the curvature of the upper portion of the cylindrical body l l of the tank and slides free of the access aperture 2|, longitudinally of the body portion II. A slideway for the cover plate is formed by the guides 23 and 24, secured to the exterior surface of the upper wall of the cylindrical body- H, see Fig. 3, and running longitudinally with the axis of the tank. The cover 22 may be slid back and forth in its slideway as required.

At the bottom of the tank, preferably spaced apart from the connection of the water supply pipe H to the tank, is a female threaded fitting 23 receiving in threaded relation therewith the pipe 24 leading to the heating system proper.

During normal operation of the hot water heating system of which this expansion tank advantageously forms a component part, Water is thus, constantly and automatically maintained at a predetermined level in the tank. Since closure of the ball-float valve is necessarily gradual as the water rises in the tank, a zone of valve closure in the upper portion of the tank is had; and symmetry of tank is retained by provision of the overflow passage therefrom at the axial center thereof.

Whereas this invention has been illustrated and described with respect to a preferred embodiment thereof, it is clearly understood that changes may be made without departing from the spirit of the invention as defined in the claims that here follow.

I claim:

1. An expansion tank for hot Water heating systems of the atmospheric type, comprising a horizontally disposed cylindrical tank having endclosure plates provided with a central opening, a ball-float valve mechanism disposed within said tank and having a ball-float lever arm extending horizontally and downwardly toward the axis of said cylinder, said ball-float valve arranged to admit make-up water to said tank and to stop water inflow thereto within predetermined levels of operation in a zone disposed substantially centrally of said tank, make-up water inflow means communicating with said valve and secured to the bottom of the tank adjacent an end thereof, water inlet means arranged for connection to said heating system and disposed at the bottom of the tank adjacent the opposite end thereof, and a substantially S-shaped discharge fitting connected to said tank at one of said central openings and terminating at a point above the normal limits of water level in the tank.

2. An expansion tank for hot water heating systems of the atmospheric type, comprising a horizontally disposed cylindrical tank having endclosure plates provided with a central opening, an aperture formed in a wall of said tank, 010- sure plate means for said aperture, a ball-float valve mechanism disposed within said tank and having a ball-float lever arm extending horizontally and downwardly toward the axis of said cylinder, said ball-float valve arranged to admit make-up water to said tank and to stop water inflow thereto within predetermined levels of operation in a zone disposed substantially centrally of said tank, make-up water inflow means communicating with said valve and supporting the same adjacent said aperture, said water inflow means being secured to the bottom of said tank near an end thereof, water inlet means arranged for connection to said heating system and disposed at the bottom of said tank in spaced relationship to said make-up water inflow means, and a substantially S-shaped water discharge means connected to said tank at one of said central openings and terminating at a point above the normal operating water level in the tank, whereby accommodation for water expansion is afforded between the said water level and the point of water overflow.

EDWARD S. CORNELL, JR. 

